A. Cover Sheet PI Name: Thomas M. Julian Division: Gynecology Phone: 263 5573 FAX: 608 265 7899 Email: [email protected] Proposal Title: Research and Development Grant-Laparoscopic Banding Device for Female Sterilization Have you identified any other extramural support or other funding to submit the completed proposal? No If “yes”, please enter name of agency/program below and attach a copy of the request for proposal or program announcement: If “no”, please list potential sources of funding that might be appropriate for your proposal. I do not think that there is another available source for small grants in this area to which I have access. Assurances: Yes No Pending Approval Human Subjects—not necessary Animals –not necessary Biological Safety—not necessary Certification: In applying for a Research and Development grant from the Dept. of Ob/Gyn, I agree, if awarded funding to all of the terms as stated in the R&D grant guidelines and to submit to the R&D Committee a report detailing the progress made on the project within the time period specified. Signature Date Electronic signature: Thomas M. Julian 11/13/07B. Project Description Background The medical instrumentation currently used to perform female tubal ligation (sterilization) surgeries through the banding technique is both inadequate in function and promotes the likelihood of tissue injury. These problems are directly associated with the Fallope-Ring Band manufactured by ACMI Corporation. Our team of engineering students is developing a device that is potentially capable of eliminating operative damage caused to the tissue due to poor instrument design, as well as improving overall ease of use for the surgeon. Dr. Thomas Julian first approached the Biomedical Engineering Design Program with the hope that we could solve the problems the current laparoscopic banding device presented. He stated that complications occur up to 20% of the time with the current product, which is far too high in a surgical procedure. Furthermore, the fallopian tube can be torn or otherwise damaged during the procedure causing excess internal bleeding and the formation of scar tissue. These complications reduce the chance that the surgery can be successfully reversed since more of the fallopian tube is damaged. Another problem with the device is the band release process. The procedure involves placing an elastomeric band over the fallopian tube to create a mechanical blockage. Sometimes, however, the band does not release correctly, requiring application of the second band, or two are placed on the same fallopian tube, requiring the physician to withdraw the device and load another band on it. This prolongs the procedure and requires more work for the surgeon. These errors need to occur less frequently in order to decrease time spent in the operating room and reduce risks for the patient. We believe that this can be accomplished by developing a new and better device to perform this procedure. New Design We have developed an instrument that allows for a gentler procedure for the patient and a more reliable band release for the surgeon. This device, shown in the figure to the left, consists of a handle, a long outer shaft that will extend into the body, the securing mechanism, and the band-releasing mechanism. The handle will be similar to the current device produced by ACMI Corporation. This includes thumb tabs to exposes the tip of the syringe to make contact with the fallopian tube. A trigger will generate suction to grab secure the fallopian tube. The syringe is then retracted to bring the fallopian tube inside the device for banding. A threaded collar attached to a push rod will gradually release one band onto the fallopian tube. The collar will require no more than 4-5 rotations to release one band. The instrument shaft that extends into the body is approximately 40cm long, 8 mm in diameter, hollow, and composed of stainless steel. To ensure that only one band is released at a time, we have designed a gelatin ring to be placed between the bands on the device. Once in the body, the gelatin should dissolve and not cause harm to the surrounding environment. The securing mechanism operates using a small syringe that will hold the fallopian tube in place. The thumb tabs slide forward, compressing a spring and allowing the syringe to be ejected from the device. CAD model of prototype [shown inserted into the laparoscopic port (orange)]. Threaded knob for band release (red), thumb tabs for movement of syringe (violet), trigger for creating and releasing suction (blue), and thumb-ring handle (yellow).Suction is then created when the trigger is pulled back. The bands are released when the pushing rod is moved forward just far enough so that one band is ejected off the device onto the fallopian tube. At this time, the surgeon should release the suction on the fallopian tube by disengaging the trigger. After both tubes are banded, the syringe is pulled back into the main column and the device is removed from the patient’s abdomen. There are several advantages to this design. Because the handle is similar to the current device used, the surgeons will not have to learn many new procedural steps to perform the surgery and will thus be more likely to use the device. The suction mechanism of securing the fallopian tube is gentler on the tube as compared to the pair of 'fingers' employed on the current AMCI device, and the method of releasing the bands onto the tubes will also be more reliable than the in current device. Current Status The project is in the prototype construction and testing phase. In the Fall '07 semester the team constructed a 2:1 scale prototype so that we could verify that our design concept works. Before we constructed the prototype we tested the suction mechanism to secure sheep fallopian tubes provided to us by Ron Magness, Ph.D., director of the UW Perinatal Labs, and graduate student Ben Sprague. We observed that very little force (0.25 N) was necessary to create a vacuum and secure the fallopian tubes to the end of the syringe and maintain a high level of suction. No visible damage or physical changes were observed to the fallopian tube until excessive force was applied (0.27 N). We obtained a 100% success rate for securing the fallopian tubes before any damage was observed. To test the band release mechanism, we acquired rubber bands with appropriate dimensions and loaded both
View Full Document
Unlocking...